4,658 research outputs found
Making public sector pensions less generous.
Public sector pensions have become ‘bogey of the moment’ for coalition government ministers, following warnings of steep increases in future obligations. Leandro Carrera explains the key issues lying behind the current alarms.
Some results on thermal stress of layered plates and shells by using Unified Formulation
This work presents some results on two-dimensional modelling of thermal stress problems in multilayered structures. The governing equations are written by referring to the Unified Formulation (UF) introduced by the first author. These equations are obtained in a compact form, that doesn't depend on the order of expansion of variables in the thickness direction or the variable description (layer-wise models and equivalent single layers models). Classical and refined theories based on the Principle of Virtual Displacements (PVD) and advanced mixed theories based on the Reissner Mixed Variational Theorem (RMVT) are both considered. As a result, a large variety of theories are derived and compared. The temperature profile along the thickness of the plate/shell is calculated by solving the Fourier's heat conduction equation. Alternatively, thermo-mechanical coupling problems can be considered, in which the thermal variation is influenced by mechanical loading. Exact closed-form solutions are provided for plates and shells, but also the applications of the Ritz method and the Finite Element Method (FEM) are presented
Political competition and societal veto players: the politics of pension reform in Southern Europe
While Southern European countries have pursued a series of pension reforms since the early 1990s, significant variation arises across them. Focusing on the concept of political replacement risk (the probability of a government being electorally punished for pursuing a given policy) and the changes in the labor movement's organizational structure, this article seeks to elucidate the differences in reform outcomes, in Italy, Greece, Portugal and Spain. Our analysis shows that significant reforms are implemented when governments face a high political replacement risk and the labor movement has undergone changes in its structure. By contrast, governments facing a stronger labor movement will generally be less effective at passing significant reforms, unless they can secure a strong support over the necessity to implement reforms
Governing the Euro area in good times and bad, Oxford University Press , Oxford 2011.
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Radial velocities and metallicities from infrared Ca II triplet spectroscopy of open clusters II. Berkeley 23, King 1, NGC 559, NGC 6603 and NGC 7245
Context: Open clusters are key to studying the formation and evolution of the
Galactic disc. However, there is a deficiency of radial velocity and chemical
abundance determinations for open clusters in the literature. Aims: We intend
to increase the number of determinations of radial velocities and metallicities
from spectroscopy for open clusters. Methods: We acquired medium-resolution
spectra (R~8000) in the infrared region Ca II triplet lines (~8500 AA) for
several stars in five open clusters with the long-slit IDS spectrograph on the
2.5~m Isaac Newton Telescope (Roque de los Muchachos Observatory, Spain).
Radial velocities were obtained by cross-correlation fitting techniques. The
relationships available in the literature between the strength of infrared Ca
II lines and metallicity were also used to derive the metallicity for each
cluster. Results: We obtain = 48.6+/-3.4, -58.4+/-6.8, 26.0+/-4.3 and
-65.3+/-3.2 km s-1 for Berkeley 23, NGC 559, NGC 6603 and NGC 7245,
respectively. We found [Fe/H] =-0.25+/-0.14 and -0.15+/-0.18 for NGC 559 and
NGC 7245, respectively. Berkeley 23 has a low metallicity, [Fe/H]
=-0.42+/-0.13, similar to other open clusters in the outskirts of the Galactic
disc. In contrast, we derived a high metallicity ([Fe/H] =+0.43+/-0.15) for NGC
6603, which places this system among the most metal rich known open clusters.
To our knowledge, this is the first determination of radial velocities and
metallicities from spectroscopy for these clusters, except NGC 6603, for which
radial velocities had been previously determined. We have also analysed ten
stars in the line of sight to King 1. Because of the large dispersion obtained
in both radial velocity and metallicity, we cannot be sure that we have sampled
true cluster members.Comment: 10 pages, 5 figures, accepted for publication in A&A (minor
modifications
Radical pension reforms after the crisis: a comparative analysis of Argentina and Greece
Scholarly attention on pension reform following the recent global financial crisis has focused primarily on cases entailing the renationalization of private pension pillars. We argue that radical pension reforms should also include instances of radical retrenchment of public pension pillars. We offer an explanation of such reforms in the aftermath of the crisis by analyzing the reforms adopted in Argentina and Greece since 2008. We demonstrate that highly indebted countries with no access to international financial markets and unsustainable pension systems can introduce radical reforms in response to short-term funding needs rather than long-term adequacy concerns. We argue that the narrow timeframe of the recent reforms raises questions about the sound footing of the new systems which may ultimately not prevent the introduction of further measures. This comparison provides insights to understand recent episodes of radical pension reforms in other countries
On Doppler tracking in cosmological spacetimes
We give a rigorous derivation of the general-relativistic formula for the
two-way Doppler tracking of a spacecraft in Friedmann-Lemaitre-Robertson-Walker
and in McVittie spacetimes. The leading order corrections of the so-determined
acceleration to the Newtonian acceleration are due to special-relativistic
effects and cosmological expansion. The latter, although linear in the Hubble
constant, is negligible in typical applications within the Solar System.Comment: 10 pages, 1 figure. Journal versio
KIC 10449976: discovery of an extreme-helium subdwarf in the Kepler field
Optical spectroscopy of the blue star KIC 10449976 shows that it is an
extremely helium-rich subdwarf with effective temperature T=40000+/-300 K and
surface gravity log g=5.3+/-0.1. Radial-velocity measurements over a five-day
timescale show an upper variability limit of ~50+/-20 km/s. Kepler photometry
of KIC 10449976 in both long and short cadence modes shows evidence for a
periodic modulation on a timescale of ~3.9 days. We have examined the
possibility that this modulation is not astrophysical but conclude it is most
likely real. We discuss whether the modulation could be caused by a low-mass
companion, by stellar pulsations, or by spots. The identification of any one of
these as cause has important consequences for understanding the origin of
helium-rich subdwarfs.Comment: Accepted by MNRA
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